#!/usr/bin/env bash
# SPDX-License-Identifier: LGPL-2.1-or-later
set -ex

# Silence warning from running_in_chroot_or_offline()
export SYSTEMD_IGNORE_CHROOT=1

systemctl=${1:-systemctl}

unset root
cleanup() {
    [ -n "$root" ] && rm -rf "$root"
}
trap cleanup exit
root=$(mktemp -d --tmpdir systemctl-test.XXXXXX)

islink() {
    test -h "$1" || return 1
    test "$(readlink "$1")" = "$2" || return 2
}

: ------enablement nonexistent--------------------------------
"$systemctl" --root="$root" enable test1.service && { echo "Expected failure" >&2; exit 1; }

: ------basic enablement--------------------------------------
mkdir -p "$root/etc/systemd/system"
cat >"$root/etc/systemd/system/test1.service" <<EOF
[Install]
WantedBy=default.target
RequiredBy=special.target
EOF

"$systemctl" --root="$root" enable test1.service
test -h "$root/etc/systemd/system/default.target.wants/test1.service"
test -h "$root/etc/systemd/system/special.target.requires/test1.service"

"$systemctl" --root="$root" reenable test1.service
test -h "$root/etc/systemd/system/default.target.wants/test1.service"
test -h "$root/etc/systemd/system/special.target.requires/test1.service"

"$systemctl" --root="$root" disable test1.service
test ! -e "$root/etc/systemd/system/default.target.wants/test1.service"
test ! -e "$root/etc/systemd/system/special.target.requires/test1.service"

: ------suffix guessing---------------------------------------
"$systemctl" --root="$root" enable test1
test -h "$root/etc/systemd/system/default.target.wants/test1.service"
test -h "$root/etc/systemd/system/special.target.requires/test1.service"

"$systemctl" --root="$root" reenable test1
test -h "$root/etc/systemd/system/default.target.wants/test1.service"
test -h "$root/etc/systemd/system/special.target.requires/test1.service"

"$systemctl" --root="$root" disable test1
test ! -e "$root/etc/systemd/system/default.target.wants/test1.service"
test ! -e "$root/etc/systemd/system/special.target.requires/test1.service"

: -------aliases----------------------------------------------
"$systemctl" --root="$root" enable test1
test -h "$root/etc/systemd/system/default.target.wants/test1.service"
test -h "$root/etc/systemd/system/special.target.requires/test1.service"

cat >>"$root/etc/systemd/system/test1.service" <<EOF
Alias=test1-goodalias.service
Alias=test1@badalias.service
Alias=test1-badalias.target
Alias=test1-badalias.socket
EOF

: -------aliases in reeanble----------------------------------
"$systemctl" --root="$root" reenable test1
test -h "$root/etc/systemd/system/default.target.wants/test1.service"
test ! -e "$root/etc/systemd/system/test1-goodalias.service"
test -h "$root/etc/systemd/system/test1-goodalias.service"

test ! -e "$root/etc/systemd/system/test1@badalias.service"
test ! -e "$root/etc/systemd/system/test1-badalias.target"
test ! -e "$root/etc/systemd/system/test1-badalias.socket"

"$systemctl" --root="$root" disable test1
test ! -e "$root/etc/systemd/system/default.target.wants/test1.service"
test ! -e "$root/etc/systemd/system/special.target.requires/test1.service"
test ! -e "$root/etc/systemd/system/test1-goodalias.service"

: -------also units-------------------------------------------
cat >"$root/etc/systemd/system/test2.socket" <<EOF
[Install]
WantedBy=sockets.target
Also=test2.service
EOF

cat >"$root/etc/systemd/system/test2.service" <<EOF
[Install]
WantedBy=default.target
Also=test2.socket
EOF

"$systemctl" --root="$root" reenable test2.service
test -h "$root/etc/systemd/system/default.target.wants/test2.service"
test -h "$root/etc/systemd/system/sockets.target.wants/test2.socket"

"$systemctl" --root="$root" reenable test2.socket
test -h "$root/etc/systemd/system/default.target.wants/test2.service"
test -h "$root/etc/systemd/system/sockets.target.wants/test2.socket"

"$systemctl" --root="$root" disable test2.socket
test ! -e "$root/etc/systemd/system/default.target.wants/test2.service"
test ! -e "$root/etc/systemd/system/sockets.target.wants/test2.socket"


: -------link-------------------------------------------------
# File doesn't exist yet
test ! -e "$root/link1.path"
"$systemctl" --root="$root" link '/link1.path' && { echo "Expected failure" >&2; exit 1; }
test ! -e "$root/etc/systemd/system/link1.path"

cat >"$root/link1.path" <<EOF
[Install]
WantedBy=paths.target
EOF

"$systemctl" --root="$root" link '/link1.path'
islink "$root/etc/systemd/system/link1.path" "/link1.path"

: -------link already linked same path------------------------
SYSTEMD_LOG_LEVEL=debug "$systemctl" --root="$root" link '/link1.path'  # this passes
islink "$root/etc/systemd/system/link1.path" "/link1.path"

: -------link already linked different path-------------------
mkdir "$root/subdir"
cp "$root/link1.path" "$root/subdir/"
"$systemctl" --root="$root" link '/subdir/link1.path' && { echo "Expected failure" >&2; exit 1; }
islink "$root/etc/systemd/system/link1.path" "/link1.path"

: -------link bad suffix--------------------------------------
cp "$root/link1.path" "$root/subdir/link1.suffix"
"$systemctl" --root="$root" link '/subdir/link1.suffix' && { echo "Expected failure" >&2; exit 1; }
test ! -e "$root/etc/systemd/system/link1.suffix"

: -------unlink by unit name----------------------------------
"$systemctl" --root="$root" disable 'link1.path'
test ! -e "$root/etc/systemd/system/link1.path"

: -------unlink by path---------------------------------------
"$systemctl" --root="$root" link '/link1.path'
test -h "$root/etc/systemd/system/link1.path"
"$systemctl" --root="$root" disable '/link1.path'
test ! -e "$root/etc/systemd/system/link1.path"

: -------unlink by wrong path---------------------------------
"$systemctl" --root="$root" link '/link1.path'
test -h "$root/etc/systemd/system/link1.path"
"$systemctl" --root="$root" disable '/subdir/link1.path'  # we only care about the name
test ! -e "$root/etc/systemd/system/link1.path"


: -------link and enable--------------------------------------
"$systemctl" --root="$root" enable '/link1.path'
islink "$root/etc/systemd/system/link1.path" "/link1.path"
islink "$root/etc/systemd/system/paths.target.wants/link1.path" "/link1.path"

: -------enable already linked same path----------------------
"$systemctl" --root="$root" enable '/link1.path'
islink "$root/etc/systemd/system/link1.path" "/link1.path"
islink "$root/etc/systemd/system/paths.target.wants/link1.path" "/link1.path"

: -------enable already linked different path-----------------
# FIXME
# "$systemctl" --root="$root" enable '/subdir/link1.path' && { echo "Expected failure" >&2; exit 1; }
# test -h "$root/etc/systemd/system/link1.path"
# readlink "$root/etc/systemd/system/link1.path"
# test -h "$root/etc/systemd/system/paths.target.wants/link1.path"
# readlink "$root/etc/systemd/system/paths.target.wants/link1.path"

: -------enable bad suffix------------------------------------
cp "$root/link1.path" "$root/subdir/link1.suffix"
"$systemctl" --root="$root" enable '/subdir/link1.suffix' && { echo "Expected failure" >&2; exit 1; }
test ! -e "$root/etc/systemd/system/link1.suffix"
test ! -e "$root/etc/systemd/system/paths.target.wants/link1.suffix"

: -------disable by unit name---------------------------------
"$systemctl" --root="$root" disable 'link1.path'
test ! -e "$root/etc/systemd/system/link1.path"
test ! -e "$root/etc/systemd/system/paths.target.wants/link1.path"

: -------disable by path--------------------------------------
"$systemctl" --root="$root" enable '/link1.path'
test -h "$root/etc/systemd/system/link1.path"
test -h "$root/etc/systemd/system/paths.target.wants/link1.path"
"$systemctl" --root="$root" disable '/link1.path'
test ! -e "$root/etc/systemd/system/link1.path"
test ! -e "$root/etc/systemd/system/paths.target.wants/link1.path"


: -------link then enable-------------------------------------
"$systemctl" --root="$root" link '/link1.path'
islink "$root/etc/systemd/system/link1.path" "/link1.path"
test ! -h "$root/etc/systemd/system/paths.target.wants/link1.path"

"$systemctl" --root="$root" enable 'link1.path'
islink "$root/etc/systemd/system/link1.path" "/link1.path"
islink "$root/etc/systemd/system/paths.target.wants/link1.path" "/link1.path"

# FIXME
# "$systemctl" --root="$root" reenable 'link1.path'
# islink "$root/etc/systemd/system/link1.path" "/link1.path"
# islink "$root/etc/systemd/system/paths.target.wants/link1.path" "/link1.path"


: -------manual link------------------------------------------
cat >"$root/link3.suffix" <<EOF
[Install]
WantedBy=services.target
EOF

ln -s "/link3.suffix" "$root/etc/systemd/system/link3.service"

# SYSTEMD_LOG_LEVEL=debug SYSTEMD_LOG_LOCATION=1 "$systemctl" --root="$root" enable 'link3.service'
# islink "$root/etc/systemd/system/link3.service" "/link3.suffix"
# islink "$root/etc/systemd/system/services.target.wants/link3.service" "../link3.service"
# unit_file_load_or_readlink() needs to be fixed to not follow links

: -------enable on masked-------------------------------------
ln -s "/dev/null" "$root/etc/systemd/system/masked.service"
"$systemctl" --root="$root" enable 'masked.service' && { echo "Expected failure" >&2; exit 1; }
"$systemctl" --root="$root" enable '/etc/systemd/system/masked.service' && { echo "Expected failure" >&2; exit 1; }

: -------enable on masked alias-------------------------------
test -h "$root/etc/systemd/system/masked.service"
ln -s "masked.service" "$root/etc/systemd/system/masked-alias.service"
"$systemctl" --root="$root" enable 'masked-alias.service' && { echo "Expected failure" >&2; exit 1; }
"$systemctl" --root="$root" enable '/etc/systemd/system/masked-alias.service' && { echo "Expected failure" >&2; exit 1; }

: -------issue 22000: link in subdirectory--------------------
mkdir -p "$root/etc/systemd/system/myown.d"
cat >"$root/etc/systemd/system/link5-also.service" <<EOF
[Install]
WantedBy=services.target
Also=link5.service
EOF
cat >"$root/etc/systemd/system/myown.d/link5.service" <<EOF
[Install]
WantedBy=services.target
Also=link5-also.service
EOF

"$systemctl" --root="$root" enable 'link5.service' && { echo "Expected failure" >&2; exit 1; }
test ! -h "$root/etc/systemd/system/services.target.wants/link5.service"
test ! -h "$root/etc/systemd/system/services.target.wants/link5-also.service"

"$systemctl" --root="$root" enable 'link5-also.service'
test ! -h "$root/etc/systemd/system/services.target.wants/link5.service"
islink "$root/etc/systemd/system/services.target.wants/link5-also.service" "/etc/systemd/system/link5-also.service"

: -------template enablement----------------------------------
cat >"$root/etc/systemd/system/templ1@.service" <<EOF
[Install]
WantedBy=services.target
EOF

# No instance here — this can't succeed.
"$systemctl" --root="$root" enable 'templ1@.service' && { echo "Expected failure" >&2; exit 1; }
test ! -h "$root/etc/systemd/system/services.target.wants/templ1@.service"

"$systemctl" --root="$root" enable 'templ1@one.service'
test ! -h "$root/etc/systemd/system/services.target.wants/templ1@.service"
islink "$root/etc/systemd/system/services.target.wants/templ1@one.service" "/etc/systemd/system/templ1@.service"

"$systemctl" --root="$root" enable 'templ1@two.service'
test ! -h "$root/etc/systemd/system/services.target.wants/templ1@.service"
islink "$root/etc/systemd/system/services.target.wants/templ1@one.service" "/etc/systemd/system/templ1@.service"
islink "$root/etc/systemd/system/services.target.wants/templ1@two.service" "/etc/systemd/system/templ1@.service"

"$systemctl" --root="$root" disable 'templ1@one.service'
test ! -h "$root/etc/systemd/system/services.target.wants/templ1@.service"
test ! -h "$root/etc/systemd/system/services.target.wants/templ1@one.service"
islink "$root/etc/systemd/system/services.target.wants/templ1@two.service" "/etc/systemd/system/templ1@.service"

"$systemctl" --root="$root" disable 'templ1@two.service'
test ! -h "$root/etc/systemd/system/services.target.wants/templ1@.service"
test ! -h "$root/etc/systemd/system/services.target.wants/templ1@one.service"
test ! -h "$root/etc/systemd/system/services.target.wants/templ1@two.service"

: -------template enablement w/ default instance--------------
cat >>"$root/etc/systemd/system/templ1@.service" <<EOF
DefaultInstance=333
EOF
# FIXME: should we deduplicate the target? Right now we warn twice if WantedBy= is repeated.
# WantedBy=services.target services.target

"$systemctl" --root="$root" enable 'templ1@.service'
test ! -h "$root/etc/systemd/system/services.target.wants/templ1@.service"
islink "$root/etc/systemd/system/services.target.wants/templ1@333.service" "/etc/systemd/system/templ1@.service"

"$systemctl" --root="$root" enable 'templ1@one.service'
test ! -h "$root/etc/systemd/system/services.target.wants/templ1@.service"
islink "$root/etc/systemd/system/services.target.wants/templ1@333.service" "/etc/systemd/system/templ1@.service"
islink "$root/etc/systemd/system/services.target.wants/templ1@one.service" "/etc/systemd/system/templ1@.service"

"$systemctl" --root="$root" enable 'templ1@two.service'
test ! -h "$root/etc/systemd/system/services.target.wants/templ1@.service"
islink "$root/etc/systemd/system/services.target.wants/templ1@333.service" "/etc/systemd/system/templ1@.service"
islink "$root/etc/systemd/system/services.target.wants/templ1@one.service" "/etc/systemd/system/templ1@.service"
islink "$root/etc/systemd/system/services.target.wants/templ1@two.service" "/etc/systemd/system/templ1@.service"

"$systemctl" --root="$root" disable 'templ1@one.service'
test ! -h "$root/etc/systemd/system/services.target.wants/templ1@.service"
islink "$root/etc/systemd/system/services.target.wants/templ1@333.service" "/etc/systemd/system/templ1@.service"
test ! -h "$root/etc/systemd/system/services.target.wants/templ1@one.service"
islink "$root/etc/systemd/system/services.target.wants/templ1@two.service" "/etc/systemd/system/templ1@.service"

# disable both remaining links here
"$systemctl" --root="$root" disable 'templ1@.service'
test ! -h "$root/etc/systemd/system/services.target.wants/templ1@.service"
test ! -h "$root/etc/systemd/system/services.target.wants/templ1@333.service"
test ! -h "$root/etc/systemd/system/services.target.wants/templ1@one.service"
test ! -h "$root/etc/systemd/system/services.target.wants/templ1@two.service"

: -------aliases w/ and w/o instance--------------------------
test ! -e "$root/etc/systemd/system/link4.service"
cat >"$root/etc/systemd/system/link4.service" <<EOF
[Install]
# FIXME: self-alias should be ignored
# Alias=link4.service
Alias=link4@.service
Alias=link4@inst.service
Alias=link4alias.service
Alias=link4alias2.service
EOF

"$systemctl" --root="$root" enable 'link4.service'
test ! -h "$root/etc/systemd/system/link4.service"  # this is our file
test ! -h "$root/etc/systemd/system/link4@.service"
test ! -h "$root/etc/systemd/system/link4@inst.service"
islink "$root/etc/systemd/system/link4alias.service" "/etc/systemd/system/link4.service"
islink "$root/etc/systemd/system/link4alias2.service" "/etc/systemd/system/link4.service"

"$systemctl" --root="$root" disable 'link4.service'
test ! -h "$root/etc/systemd/system/link4.service"
test ! -h "$root/etc/systemd/system/link4@.service"
test ! -h "$root/etc/systemd/system/link4@inst.service"
test ! -h "$root/etc/systemd/system/link4alias.service"
test ! -h "$root/etc/systemd/system/link4alias2.service"

: -------systemctl enable on path to unit file----------------
# Apparently this works. I'm not sure what to think.
"$systemctl" --root="$root" enable '/etc/systemd/system/link4.service'
test ! -h "$root/etc/systemd/system/link4.service"  # this is our file
test ! -h "$root/etc/systemd/system/link4@.service"
test ! -h "$root/etc/systemd/system/link4@inst.service"
islink "$root/etc/systemd/system/link4alias.service" "/etc/systemd/system/link4.service"
islink "$root/etc/systemd/system/link4alias2.service" "/etc/systemd/system/link4.service"

"$systemctl" --root="$root" disable '/etc/systemd/system/link4.service'
test ! -h "$root/etc/systemd/system/link4.service"
test ! -h "$root/etc/systemd/system/link4@.service"
test ! -h "$root/etc/systemd/system/link4@inst.service"
test ! -h "$root/etc/systemd/system/link4alias.service"
test ! -h "$root/etc/systemd/system/link4alias2.service"

: -------issue 661: link and enable on unit file--------------
test ! -e "$root/etc/systemd/system/link5.service"
cat >"$root/etc/systemd/system/link5.service" <<EOF
[Install]
# FIXME: self-alias should be ignored
# Alias=link5.service
Alias=link5@.service
Alias=link5@inst.service
Alias=link5alias.service
Alias=link5alias2.service
EOF

"$systemctl" --root="$root" enable 'link5.service'
test ! -h "$root/etc/systemd/system/link5.service"  # this is our file
test ! -h "$root/etc/systemd/system/link5@.service"
test ! -h "$root/etc/systemd/system/link5@inst.service"
# FIXME/CLARIFYME: will systemd think that link5alias2, link5alias, link5 are all aliases?
# https://github.com/systemd/systemd/issues/661#issuecomment-1057931149
islink "$root/etc/systemd/system/link5alias.service" "/etc/systemd/system/link5.service"
islink "$root/etc/systemd/system/link5alias2.service" "/etc/systemd/system/link5.service"

"$systemctl" --root="$root" disable 'link5.service'
test ! -h "$root/etc/systemd/system/link5.service"
test ! -h "$root/etc/systemd/system/link5@.service"
test ! -h "$root/etc/systemd/system/link5@inst.service"
test ! -h "$root/etc/systemd/system/link5alias.service"
test ! -h "$root/etc/systemd/system/link5alias2.service"

: ----issue 19437: plain templates in .wants/ or .requires/---
test ! -e "$root/etc/systemd/system/link5@.path"
cat >"$root/etc/systemd/system/link5@.path" <<EOF
[Install]
WantedBy=target5@.target
RequiredBy=target5@.target
WantedBy=target5@inst.target
RequiredBy=target5@inst.target
EOF

"$systemctl" --root="$root" enable 'link5@.path'
test ! -h "$root/etc/systemd/system/link5@.path"  # this is our file
islink "$root/etc/systemd/system/target5@.target.wants/link5@.path" "/etc/systemd/system/link5@.path"
islink "$root/etc/systemd/system/target5@.target.requires/link5@.path" "/etc/systemd/system/link5@.path"
islink "$root/etc/systemd/system/target5@inst.target.wants/link5@.path" "/etc/systemd/system/link5@.path"
islink "$root/etc/systemd/system/target5@inst.target.requires/link5@.path" "/etc/systemd/system/link5@.path"

"$systemctl" --root="$root" disable 'link5@.path'
test ! -h "$root/etc/systemd/system/link5@.path"  # this is our file
test ! -h "$root/etc/systemd/system/target5@.target.wants/link5@.path"
test ! -h "$root/etc/systemd/system/target5@.target.requires/link5@.path"
test ! -h "$root/etc/systemd/system/target5@inst.target.wants/link5@.path"
test ! -h "$root/etc/systemd/system/target5@inst.target.requires/link5@.path"

: -------removal of symlinks not listed in [Install]----------
# c.f. 66a19d85a533b15ed32f4066ec880b5a8c06babd
test ! -e "$root/etc/systemd/system/multilink.mount"
cat >"$root/etc/systemd/system/multilink.mount" <<EOF
[Install]
WantedBy=multilink.target
EOF

mkdir -p "$root/etc/systemd/system/default.target.wants"
ln -s ../multilink.mount "$root/etc/systemd/system/default.target.wants/"
ln -s ../multilink.mount "$root/etc/systemd/system/multilink-alias.mount"
ln -s ../multilink.mount "$root/etc/systemd/system/multilink-badalias.service"

"$systemctl" --root="$root" disable 'multilink.mount'
test -e "$root/etc/systemd/system/multilink.mount"  # this is our file
test ! -h "$root/etc/systemd/system/default.target.wants/"
test ! -h "$root/etc/systemd/system/multilink-alias.mount"
test ! -h "$root/etc/systemd/system/multilink-badalias.service"

: -------merge 20017: specifiers in the unit file-------------
test ! -e "$root/etc/systemd/system/some-some-link6@.socket"
# c.f. de61a04b188f81a85cdb5c64ddb4987dcd9d30d3

check_alias() {
    : ------------------ %$1 -------------------------------------
    cat >"$root/etc/systemd/system/some-some-link6@.socket" <<EOF
[Install]
Alias=target@$1:%$1.socket
EOF
    SYSTEMD_LOG_LEVEL=debug "$systemctl" --root="$root" enable 'some-some-link6@.socket' || return 1
    islink "$root/etc/systemd/system/target@$1:$2.socket" "/etc/systemd/system/some-some-link6@.socket" || return 2
}

check_alias a "$(uname -m | tr '_' '-')"

test ! -e "$root/etc/os-release"
test ! -e "$root/usr/lib/os-release"

check_alias A '' && { echo "Expected failure" >&2; exit 1; }
check_alias B '' && { echo "Expected failure" >&2; exit 1; }
check_alias M '' && { echo "Expected failure" >&2; exit 1; }
check_alias o '' && { echo "Expected failure" >&2; exit 1; }
check_alias w '' && { echo "Expected failure" >&2; exit 1; }
check_alias W '' && { echo "Expected failure" >&2; exit 1; }

cat >"$root/etc/os-release" <<EOF
# empty
EOF

check_alias A ''
check_alias B ''
check_alias M ''
check_alias o ''
check_alias w ''
check_alias W ''

cat >"$root/etc/os-release" <<EOF
ID='the-id'
VERSION_ID=39a
BUILD_ID=build-id
VARIANT_ID=wrong
VARIANT_ID=right
IMAGE_ID="foobar"
IMAGE_VERSION='1-2-3'
EOF

check_alias A '1-2-3'
check_alias B 'build-id'
check_alias M 'foobar'
check_alias o 'the-id'
check_alias w '39a'
check_alias W 'right'

check_alias b "$(systemd-id128 boot-id)"

# Specifiers not available for [Install]
check_alias C '' && { echo "Expected failure" >&2; exit 1; }
check_alias E '' && { echo "Expected failure" >&2; exit 1; }
check_alias f '' && { echo "Expected failure" >&2; exit 1; }
check_alias h '' && { echo "Expected failure" >&2; exit 1; }
check_alias I '' && { echo "Expected failure" >&2; exit 1; }
check_alias J '' && { echo "Expected failure" >&2; exit 1; }
check_alias L '' && { echo "Expected failure" >&2; exit 1; }
check_alias P '' && { echo "Expected failure" >&2; exit 1; }
check_alias s '' && { echo "Expected failure" >&2; exit 1; }
check_alias S '' && { echo "Expected failure" >&2; exit 1; }
check_alias t '' && { echo "Expected failure" >&2; exit 1; }
check_alias T '' && { echo "Expected failure" >&2; exit 1; }
check_alias V '' && { echo "Expected failure" >&2; exit 1; }

# FIXME: we use the calling user instead of root :(
check_alias g root || :
check_alias G 0 || :

check_alias i ""

check_alias j 'link6'

check_alias l "$(uname -n | sed 's/\..*//')"

test ! -e "$root/etc/machine-id"
check_alias m '' && { echo "Expected failure" >&2; exit 1; }

systemd-id128 new >"$root/etc/machine-id"
check_alias m "$(cat "$root/etc/machine-id")"

check_alias n 'some-some-link6@.socket'
check_alias N 'some-some-link6@'

check_alias p 'some-some-link6'

# FIXME: we use the calling user instead of root :(
check_alias u root || :
check_alias U 0 || :

check_alias v "$(uname -r)"

check_alias % '%' && { echo "Expected failure because % is not legal in unit name" >&2; exit 1; }

check_alias z 'z' && { echo "Expected failure because %z is not known" >&2; exit 1; }

# FIXME: if there's an invalid Alias=, we shouldn't preach about empty [Install]

# TODO: repeat the tests above for presets

: -------SYSTEMD_OS_RELEASE relative to root------------------
# check that os-release overwriting works as expected with root
test -e "$root/etc/os-release"

cat >"$root/etc/os-release2" <<EOF
ID='the-id2'
EOF

SYSTEMD_OS_RELEASE="$root/etc/os-release2" check_alias o 'the-id2'